JP3600991B2 - Reinforcement embankment method using geotextile - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a reinforcing embankment method using geotextile.
[0002]
[Problems to be solved by the invention]
In recent years, in the case of embankments formed on the mountain side etc. by cutting out the sloped ground, geotextiles are used as embankment materials mainly in the field generated by the notch, and the geotextile becomes multiple steps up and down during the embankment While laying in this way, one end (slope side) of the geotextile is wrapped up and the earth wall material located on that one end side (the embankment material may be used as it is as the earth wall material) is rolled in. The geotextile is reinforced as an embankment reinforced with the geotextile, and the earth wall forming the slope is also becoming a reinforced earth wall supported by the geotextile.
[0003]
By the way, it is not always possible that the soil generated at the site can be a good embankment material because the soil generated at the site is a highly water-containing viscous soil or a frost-heaving soil. For this reason, for example, it takes time and effort to form the earth wall portion of the embankment in order to make the earth wall portion stable, and in order to secure a predetermined fixing property to the geotextile, the entire embankment is made of high quality soil. In order to construct a predetermined reinforcing embankment, labor and cost are required. That is, there is the following problem from the present state of the reinforcing embankment in which such a high quality embankment material cannot be obtained.
For example, when greening the slope part as a slope finish, a method of rolling the vegetation sandbags with geotextile and a steel frame method of placing a steel frame on the slope and attaching a vegetation mud to it are proposed. However, the above-mentioned vegetation sandbag method requires a lot of labor for production and laying of the vegetation sandbag, so that it is difficult to perform mechanized construction, and there is a problem that the construction period is prolonged in the sandbag loading operation. In addition, the steel frame method is expensive, and there is a problem that it is difficult to freely form a smooth slope in conformity with terrain such as mountainous land where there are many changes.
When a high water content viscous soil is used as the embankment material, a geotextile made of an expensive nonwoven fabric having both a drainage reinforcing effect and a tensile strength effect must be used. On the other hand, there is a case where the soil generated at the site is the highly water-containing viscous soil, and the use of the soil as the embankment material is abandoned. In other words, if the embankment material is only a highly water-containing viscous soil, the pull-out resistance and the frictional resistance of the geotextile are insufficient, and the safety factor against slipping is difficult to secure. In this case, not only is it uneconomical to prepare another good-quality soil, but also there is a problem in the treatment of the highly hydrated clayey soil that is the locally generated soil.
In addition, if the soil used as embankment material is frost-heaving material such as highly water-containing viscous soil, freezing in the winter will cause frost heaving and freeze-freeze on the geotextile laid in the frost-heaving material. There has been a problem that the force acts and breaks or pulls out. For example, FIG. 5 shows an example. In order to reinforce the embankment a, a method of installing the reinforcing material b such as the above-mentioned geotextile inside the embankment a is adopted. In a cold region such as Hokkaido, a frozen surface c enters the embankment from the ground surface or the slope side. And may freeze to near 2.0 m. If the generated soil is non-frost-absorbing sand or gravel as the embankment material, even if it freezes, the frost heaving will be very small, so if proper treatment of groundwater is not a serious problem. However, if the soil generated at the site as an embankment material is a frost-heaving material such as a highly hydrated viscous soil, frost heaving occurs due to freezing, and the frost-freezing frost heaving force d acts on the reinforcing material such as geotextile, causing breakage and pulling out. The inconvenience has occurred. In fact, in Hokkaido, when the slope was reinforced by an earth anchor, the anchor might break or be pulled out due to frost heave.
[0004]
In view of the above circumstances, it is an object of the present invention to make it possible to construct a reinforcing embankment economically, to facilitate the finishing of a slope on a reinforcing embankment wall of a reinforcing embankment, and to make sure that the geotextile in the embankment is properly reinforced. The purpose is to make it function.
[0005]
[Means for Solving the Problems]
The present invention has been made in consideration of the above problems, and lays a plurality of geotextiles in an embankment in a plurality of upper and lower stages, and wraps and reinforces a soil wall material disposed on one end side of each of the geotextiles with the geotextile. In the reinforcing embankment method of providing an earth wall, at least at a place where the geotextile is laid, a non-frost-free part made of a non-frost-resistant material that covers the geotextile between the reinforcing soil wall and the freezing depth or more is provided. An object of the present invention is to provide a reinforcing embankment method using geotextiles.
Further, another invention is a reinforcing embankment in which a plurality of geotextiles are laid in an embankment in a plurality of upper and lower stages, and a soil wall material arranged on one end side of each of the geotextiles is wound with the geotextile to provide a reinforcing earth wall. In the method, the reinforced earth wall has a thickness at least extending from a slope of the reinforced earth wall to a freezing depth, and the entire reinforced earth wall is formed by making the earth wall material of the reinforced earth wall non-freezing material. a reinforcing embankments method using a geotextile which is characterized in that a non-frost heaving of unit, to provide this reinforcement embankment method, Ru der which solve the above problems.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
It will be described in detail with reference now to the present invention from Figure 1 in the embodiment shown in FIG.
FIGS. 1 to 3 show a first example in which a reinforcing embankment 1 is constructed on the mountain side of the ground A that has been cut. The reinforcing embankment 1 is composed of embankment materials 2 made of on-site generated soil and geotextiles 3 laid alternately in the vertical direction. A plurality of geotextiles 3 are laid in a plurality of steps vertically at predetermined intervals, and one end 4 of each of the geotextiles 3 on the side of the slope 7 is rolled up, and the earth wall material 5 is wound therein. In addition, a reinforcing earth wall 6 is provided by connecting the earth wall material 5 in the winding portion vertically. In the first example, the non-freezing portion 10 made of a non-freezing material that covers the geotextile 3 from the reinforced soil wall 6 to the freezing depth or more is provided at the place where the geotextile 3 is laid. Is what it is.
The reinforcing embankment 1 in the example shown in FIG. 1 is provided with a plurality of upper and lower holding layers 9 made of high quality soil for holding the geotextile 3, and the embankment material 2 between the holding layers 9 is a site such as clayey soil. The excavated soil is used. In the portion where the geotextile 3 is buried, the area between the reinforced earth wall 6 and the freezing depth of 11 or more serves as the non-freezing portion 10. The non-frosting material used in the non-frosting portion 10 as a measure against frost heaving is a stabilized soil described below (however, a cement addition rate of 15 to 20%: in order to make the highly water-containing viscous soil non-frosting, An addition rate of 15 to 20% is required) or sand or gravel is used. As described above, the stabilized soil in the non-frosting part 10 can be used as a high-quality soil for holding the geotextile tile as described above, and can also be used as a non-frosting material for measures against frost heave. them to holding layer continuous with the rear surface of the mud 6 this treated soil can be the holding layer is configured as that combines also the non-frost heaving of section 10. Although the reinforced earth wall 6 in the reinforced embankment 1 shown in FIG. 1 uses the vegetation sandbag 12 as an earth wall material, it is not limited to this.
[0007]
In the example shown in FIG. 1, the embankment material 2 between the non-frost-heavy portions 10 is a normal embankment material and may be a highly water-containing viscous soil. For this reason, the reinforced earth wall 6 may receive the frost heaving force d from the back side between the non-frost heaving portions 10. However, one end 4 of the geotextile tile 3 in which the reinforced earth wall 6 is wound is free from restraint as compared with the buried part and has play, so that the frost heave force is absorbed by the play. Can be.
FIG. 2 shows a modification of the reinforced embankment 1 shown in FIG. 1 described above. Similarly, a reinforced earth wall 6 is formed from a vegetation sandbag 12. In addition, in the reinforced embankment 1 shown in FIG. 2, the freezing depth is not less than 11 from the back of the reinforced earth wall 6 even at a portion other than the portion where the geotextile 3 is laid, that is, between the upper and lower geotextiles 3. The non-frosting part 13 is provided by the non-frosting material made of the above-mentioned stabilized soil or sand and gravel, and the non-frosting part 10 arranged on the entire back side of the reinforced soil wall 6 is provided. , And 13 are provided at a depth of the freezing depth of 11 or more and are provided so that freezing does not occur.
[0008]
FIG. 3 shows an example in which only the reinforced earth wall 6 in the reinforced embankment 1 shown in FIG. 1 is changed, and the reinforced earth wall 6 uses the stabilized soil as the earth wall material 5 and has a slope. 7 is greened by arranging a vegetation mat 8 or employing a spraying method. In the reinforced embankment 1 having the reinforced earth wall using the stabilized soil as the earth wall material, the reinforced earth wall 6 receives the frost heave force d from the back side as in the example shown in FIG. There is play at one end 4 of 3 for the above-described reason, and the freezing / freezing force is absorbed by the play. In addition, the thickness of the reinforcing earth wall 6 is 0.5 to 0.8 m.
[0009]
The stabilized soil in each of the above examples is obtained by mixing a shape retaining agent such as cement or lime with viscous soil generated by cutting the ground A. The soil treated with the earth wall material has characteristics that can be easily shaped at the initial stage of the mixing of the shape-retaining agent. Each time the embankment material 2 is embanked, the soil is stabilized on the slope side of the geotextile 3. The soil is laid, and the stabilized soil is shaped by a backhoe slope bucket or the like to form a required slope.
[0010]
FIG. 4 shows a second example. Even in the reinforced embankment 1 of the second example, a plurality of geotextiles 3 are laid up and down in a plurality of steps similarly to the above examples, and one end 4 of each of the geotextiles 3 on the side of the slope 7 is provided. Is wound up, and the earth wall material 5 is rolled up. The earth wall material 5 at the rolled-up portion is vertically continuous, so that the reinforcing earth wall 6 is provided. In the reinforced embankment 1 in the second example, the reinforced earth wall 6 is made of a stabilized treated soil which is a non-freezing material as in the example shown in FIG. It is greened by arranging the vegetation mat 8 or adopting the spraying method. The reinforced soil wall 6 of this example has a thickness of not less than a freezing depth of 11 and the entire reinforced soil wall is a non-frosting portion, thereby preventing frost heaving.
The geotextile 3 in the embankment has been buried in the holding layer 9 from the back side of the reinforced earth wall 6. This retaining layer 9 is made of good-quality soil made of gravel, sandy soil, or stabilized soil, as in the case of the above example. However, since the reinforced earth wall is made of stabilized soil and its thickness is sufficiently large, the reinforced earth wall itself securely holds the geotextile, ensuring pull-out resistance and frictional resistance. It is not something.
[0011]
As described above, in the example shown in FIG. 4, since the soil wall material has a thickness up to the freezing depth, the earth wall material is made of a non-freezing material, and the entire reinforced soil wall is made of a non-freezing portion, the freezing acting on the geotextile is performed. Generation of frost heave force is suppressed, and breakage and pull-out of the geotextile can be prevented.
[0012]
【The invention's effect】
According to the present invention described above, a plurality of geotextiles are laid in the embankment in upper and lower stages, and the earth wall material disposed on one end side of each of the geotextiles is wound around the geotextile to provide a reinforcing earth wall. In the embankment method, at least at the place where the geotextile is laid, the non-frozen portion made of a non-frozen material covering the geotextile is provided between the reinforced soil wall and the freezing depth or more. Without frost heaving force, breakage and pull-out are eliminated, and pull-out resistance and friction resistance are secured.
Furthermore, the reinforced earth wall has a thickness that extends at least from the slope of the reinforced earth wall to the freezing depth, and the reinforced earth wall is made of a non-frost-free material to make the entire reinforced earth wall non-freezing. By using the frost heaving portion, frost heaving does not occur on the reinforced soil wall side, and it is possible to prevent the geotextile from breaking or pulling out, thereby achieving an effect with excellent practicality.
[Brief description of the drawings]
FIG. 1 is an explanatory view showing a reinforced embankment in which a non-freezing portion is provided at a geotextile laying point in a first example of a reinforced embankment method using a geotextile according to the present invention.
FIG. 2 is an explanatory view showing a reinforced embankment in which a non-frosting portion is provided between geotextile laying points in a first example .
FIG. 3 is an explanatory view showing a reinforced embankment in which a soil wall material of a reinforced earth wall is a stabilized soil in the first example .
FIG. 4 is an explanatory diagram showing a reinforcing embankment of a second example .
FIG. 5 is an explanatory view showing a reinforced embankment provided with a conventional geotextile .
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Reinforcement embankment 2 ... Embankment material 3 ... Geotextile 5 ... Earth wall material 6 ... Reinforcement earth wall 7 ... Slope 9 ... Retention layer 10, 13 ... Non-freezing part 11 ... Freezing depth

Claims (2)

In the reinforcing embankment method of laying a plurality of geotextiles in the embankment in a plurality of steps up and down, and embedding the earth wall material arranged on one end side of each of the geotextiles with the geotextile to provide a reinforcing earth wall,
A reinforcing embankment method using a geotextile, characterized in that at least a place where the geotextile is laid, a nonfreezing part made of a nonfreezing material is provided to cover the geotextile from the reinforcing soil wall to a depth not lower than the freezing depth . In the reinforcing embankment method of laying a plurality of geotextiles in the embankment in a plurality of steps up and down, and embedding the earth wall material arranged on one end side of each of the geotextiles with the geotextile to provide a reinforcing earth wall,
The reinforced soil wall has a thickness ranging from at least the slope of the reinforced soil wall to the freezing depth, and the reinforced soil wall is made of a non-frosting material to make the entire reinforced soil wall non-frosting. Reinforcement embankment method using geotextile, characterized by having a part .

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